Hi,

i have a sensitive manometer (from a biosafety cabinet) that i keep  
meaning to use in mapping low pressure areas on van. It has 2 inlets  
that can be attached to tubing. one inlet can be thought of as  
reference, end placed somewhere. the other inlet can then be placed  
in various areas to get an idea of relative pressure differences.

I wanted to see what the differences were around the inlet scoops, at  
various van speeds. I will get around to it sometime.

I do know that pretty well the entire rear hatch is low pressure.  
That comes from observing a really badly smoking van, the smoke  
"trapped" at the back quite plainly. Also the dirt deposition on  
back, and the various reports (one firsthand, years ago popped a  
filter seal) of oil spray on back.

I hope to do the pressure testing soon.

Alistair

On 27-Feb-07, at 9:50 AM, David Marshall wrote:

I am thinking of doing some performance mods to my TriStar that has a
115hp pumpe d�se TDI when the insurance is up in late April.  I
have a VNT-22 turbo here and will be building a custom exhaust manifold
for it and will be beefing up the intercooler from the "AHU" so
that I have to something larger to handle the additional air
compression.  I have my eye on the LT-II / Sprinter intercooler which
is about 4x to 5x larger than the AHU intercooler.  The problem for
me is where to mount the intercooler on a Syncro where there will be
sufficient air flow to cool it down when there is 1.6bar of air pressure
running though it.  Currently I have an aluminium plate over the
driver side tail light area that the AHU intercooler is attached to.
This is all sealed off and an 8" fan is behind it to force the cold
outside air through it and into the engine compartment.  I am
thinking that the Sprinter intercooler will be as long as the engine
compartment is from front to rear and still leave some room for the
piping.  I was thinking I could build a sheet metal ducting around
one side of the intercooler so the same fan would continue to push only
cold air through it and not the warm engine bay air.  I was also
thinking of ways to improve this and was wondering if there is any  
natural
low pressure zones at the back of a Vanagon to assist pulling the air
through the intercooler?  Is the engine bay a natural low pressure
zone as compared to the outside of the van?  If I extend an
additional ducting downwards to where the air under the van is moving  
will
that create a small vacuum?

David Marshall

http://www.hasenwerk.ca
http://www.fastforward.ca

Box
4153, Quesnel BC, Canada V2J 3J2